| Acronym | Meaning |
![](file.png) | IRMPA | Infrared Multiphoton Absorption |
![](file.png) | IRMPD | Infrared Multiphoton Dissociation |
![](file.png) | IRMS | Isotope Ratio Mass Spectrometry |
![](file.png) | IRN | Indicator Radionuclide |
![](file.png) | IRP | Installation Restoration Program |
![](file.png) | IRP | Internal Reflection Photolysis |
![](file.png) | IRPDS | Infrared Photothermal Deflection Spectroscopy |
![](file.png) | IRPTC | International Register Of Potentially Toxic Chemicals |
![](file.png) | IRR | Internal Rate Of Return |
![](file.png) | IRRAS | Infrared Reflection Absorption Spectroscopy |
![](file.png) | IRRAS | Integrated Reliability And Risk Analysis System |
![](file.png) | IRRI | International Rice Research Institute |
![](file.png) | IRRS | IR Reflection Spectroscopy |
![](file.png) | IRS | Infrared Soldering |
![](file.png) | IRS | Insulin Receptor Substrate |
![](file.png) | IRS | Interferon-responsive Sequence |
![](file.png) | IRS | Internal Recognition Subsequence |
![](file.png) | IRS | Internal Reflection Spectroscopy |
![](file.png) | IRS | Inverse Raman Scattering |
![](file.png) | IRSID | French Research Institute Of Siderurgy |
![](file.png) | IRSL | IR Stimulated Luminescence |
![](file.png) | IRTF | NASA Infrared Telescope Facility |
![](file.png) | IRZ | Immediate Response Zone |
![](file.png) | IS | Ionization Spectroscopy |
![](file.png) | ISA | Instrument Society Of America |
![](file.png) | ISA | Ionic Strength Adjuster |
![](file.png) | ISAAC | International Study Of Asthma And Allergies In Childhood |
![](file.png) | ISAM | Ionically Self-assembled Monolayer |
![](file.png) | ISAMS | Improved Stratospheric And Mesospheric Sounder |
![](file.png) | ISAS | Japanese Institute Of Space And Astronomical Science |
![](file.png) | ISAST | Irreversible Sorption Affected Solute Transport [model] |
![](file.png) | ISAT | In Situ Adaptive Tabulation |
![](file.png) | ISAW | Interactive Self-avoiding Walk [modeling] |
![](file.png) | ISBN | International Standard Book Number |
![](file.png) | ISC | Industrial Source Complex |
![](file.png) | ISC | Initial Safe Concentration |
![](file.png) | ISC | Intersystem Crossing |
![](file.png) | ISC | Short-circuit Current |
![](file.png) | ISC-PEM-MO | Iterative Self-consistent Partition Of Energy Method And MO Formalism |
![](file.png) | ISC3 | Industrial Source Complex Version 3 |
![](file.png) | ISCA | Ionization Spectroscopy For Chemical Analysis |
![](file.png) | ISCAT | Investigation Of Sulfur Chemistry In The Antarctic Troposphere |
![](file.png) | ISCC | Intergranular Stress-corrosion Cracking |
![](file.png) | ISCCP | International Satellite Cloud Climatology Project |
![](file.png) | ISCI | Initial-state Configuration Interaction |
![](file.png) | ISCLT | Industrial Source Complex Long Term (dispersion Model) |
![](file.png) | ISCN | International System For Human Cytogenetic Nomenclature |
![](file.png) | ISCRF | Inhomogeneous Self-consistent Reaction Field Theory |
![](file.png) | ISCST | Industrial Source Complex Short Term Model (US EPA) |
![](file.png) | ISD | Inclined Substrate Deposition |